Jessica Jung loves her bestfriend, Choi Seunghyun. Unfortunately, Seunghyun dated other girl, her bestfriend Tiffany Hwang. It was too much to bear so she went away, without saying any word to her friends. Is that the only reason why she left? Fate twisted their past, will they be together? What about their "Promise Kiss"?

JC (Jessica Jung) was so sure herself that she is a LESBIAN and she wants a girl (in fact she has a girlfriend, Kwon Yuri) but that was until she met the great Choi Seunghyun. They pretended that they're are 'couple' to stop the engagement and later on, find herself being engage in him.   Choi Seunghyun was stuck in the engagement. Jessica help him to stop the engagement. He successfully get off from that engagement only to find himself in stuck in another 'unwanted engagement